This invention relates to a communication apparatus.
In cloud computing (hereinafter, abbreviated as cloud), a server in a data center is accessed from remote sites; accordingly, a network among the sites and the data center is requisite. In many cases, the network used in the cloud for consumers is the Internet and the network used in the cloud for businesses is a virtual network system including VPNs (Virtual Private Networks) in view of security and network performance.
For a plurality of virtual networks to coexist in a single physical network, a system ensuring independencies of the virtual networks is necessary.
Telecommunications carriers use wide area Ethernet (registered trademark; the same applies hereinafter) employing a technology called extended VLAN tagging (VLAN stands for Virtual Local Area Network) or provider bridging (802.1Q-in-802.1Q, Q-in-Q, double tagging) standardized by IEEE 802.1ad to achieve the independencies of virtual networks. As to the extended VLAN tagging, refer to The Evolution of Carrier Ethernet Services—Requirements and Deployment Case Studies, Luyuan Fang et al., IEEE Communications Magazine, March, 2008, pp. 69-76.
The extended VLAN tagging is a technology that adds another VLAN tag to a VLAN tagged Ethernet Frame to make communications using Ethernet Frames including multiple VLAN tags.
The VLAN tag of an Ethernet Frame which is added on the outer side of the Ethernet Frame is called STAG (Service TAG). The network apparatuses for extended VLAN tagged communication identify virtual networks for individual companies (tenants) by S-VLANs identified by STAGs to distribute Ethernet Frames to the individual virtual networks.
The VLAN tag of an Ethernet Frame which is added on the inner side than the STAG (on the payload-side of the Ethernet Frame) is called CTAG (Customer TAG). The network apparatuses for extended VLAN tagged communication identify individual networks in a business (tenant) by C-VLANs identified by CTAGs to distribute Ethernet Frames to individual office networks.
As described above, the extended VLAN tagged communication can be assured of independencies of networks among tenants and in each tenant by the STAG and the CTAG.
In the meanwhile, a telecommunications carrier uses a system called appliance (network appliance) specialized for a specific function to provide the tenants with a cloud communication service. Examples of the appliance include a WOC (Wide Area Network Optimization Controller) or a WAN accelerator for improving the communication speed between data centers or sites, an IDS/IPS (Intrusion Detection System/Intrusion Protection System) or a FW (FireWall) for detecting or blocking an abnormal communication, and a session load balancer. The functions of these systems can improve the communication function and communication performance of the cloud. Accordingly, in the following description, cloud communication services having these functions are generally called communication services as a matter of convenience.
The appliances for providing communication services include quite a number of appliances which do not support network virtualization. For this reason, it is common to install such appliances in a site of a company or a data center logically configured to be private within a company.
However, for a telecommunications carrier to provide a plurality of companies (tenants) with a communication service as one of the cloud functions, it is expected that the appliance be installed in a shared apparatus having a function of a gateway in a switching office or a data center of the telecommunications carrier. The telecommunications carrier is required to configure the appliance for different virtual networks of individual companies (tenants).
For a telecommunications carrier to provide a plurality of client companies (multiple tenants) with a communication service such as WAN optimization as one of the cloud services, it is desirable to use at least one communication apparatus that can provide a plurality of communication services while assuring the tenants of independencies of both of their respective communications by virtual network system such as wide area Ethernet and communication services.
To assure the tenants of independencies of their respective network communications, extended VLAN tagged communication is employed. For a single communication apparatus to provide a plurality of services, the communication apparatus is required to run a plurality of virtual machines. Accordingly, it is desirable to use the extended VLAN tagged communications in coordination with the communication services executed in the virtual machines and vice versa.
To use extended VLAN tagged communications in coordination with the virtual machines in executing communication services, it is required to install different virtual machines for individual tenants and individual communication services in the communication apparatus.
The existing technology has a problem to be solved: To provide a suitable starting image matching a hardware configuration of a PC to be booted via a network (refer to JP 2006-011506 A).
JP 2006-011506 A provides a solution: Based on hardware configuration information sent from a boot node 200, a starting image selection part 101 in a boot server 100 selects a starting image matching the hardware configuration information from the starting images stored in a starting image storage part 200 and transfers it to a starting image selection part 103. The starting image selection part 103 returns the selected starting image to the boot node 200. In this way, the starting image matching the hardware configuration of the boot node 200 can be provided.
The existing technology has another problem to be solved: To allow high speed deployment processing when a plurality of VMs are deployed from one template (refer to JP 2009-230655 A).
JP 2009-230655 A provides a solution: The deployment acceleration system of the virtual machine is provided with: a server 100 having a virtual machine 132; storages 300-360 which store entity of the virtual machine 132 as a virtual disk 302; and a management server 200 which controls the server 100 and the storages 300-360, wherein the storage 300 has the template 301 in which an OS (Operating System) and applications used for the virtual disk are integrated, creates a plurality of duplicates of the template 301, distributes the duplicated templates to other storages. The other storages perform VM (Virtual Machine) deployment for installing individual information about the virtual machine including an IP address and a name of a computer to the duplicated templates. The management server 200 controls each storage so that all the number of times of VM deployment and all the number of times of duplication of the templates may be minimized.